texture mapping in cycles for game model
Found the answer my self.
Here is the link to the youtube video: https://www.youtube.com/watch?v=XO9gOeDcgzg

this method will help to consolidate uv's and create one single texture material and it can be used in unity.

hope it helps someone. I asked it my self but no one answered, may be they didn't understand what I meant. anyway....this is what I wanted.....